In 1980 the F12 received the new TD120F intercooled engine and simultaneously Volvo introduced their heavy-duty SR70 12-speed gearbox to go with it. This had three gear positions each with high/low range plus splitter. There was also a crawler gear and reverse. To be precise there were two crawlers available and four reverse ratios. The TD120F developed 385bhp according to Volvo’s figures but net output to BSAU 141a was 355bhp.
Front axle capacity was raised to 7.5 tonnes in 1981 and the following year the F10 was given the more powerful TD100G with 276bhp (257 net). Transmission choice included the R62, SR62 splitter and the MR62B withmainly at heavy duty 6x4s which could operate at up to 150 tonnes gtw on heavy haulage.
